Dynamo-electric machine



R. E. HELLMUND. DYNAMO ELECTRICMACHINE- APPLICATION FILED MAR. 7, 1916.

1 49,377, Patented Aug. 10, 1920.

WITNESSES lNVENTOR RudoZf E. Hellmund.

ATTORNEY UNITED STATES PATENT OFFICE.

RUDOLF E. HELLMUN D, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENN- SYLVANIA.

DYNAMO-ELECTRIC MACHINE.

Specification of Letters Patent.

Patented Aug. 10, 1920.

To all whom it may concern:

Be it known that I, RUDOLF E. HELL- MUND, a subject of the German Emperor, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Dynamo-Electric Machines, of which the following is a specification.

My invention relates to dynamo-electric machines and particularly to machines embodying a closed-circuit winding and an energizing winding.

The object of my invention is to provide a dynamo-electric machine of the class under consideration with a closed-circuit winding that may be positioned near the surface of the magnetizable core.

Another object of my invention is to pro vide a closed-circuit winding of the aboveindicated class with end connectors that do not interfere with accessibility to the energizing winding.

A further object of my invention is to provide means for absorbing stresses in bar conductors caused by temperature changes therein."

A further object of my invention is to insure the advantages of a familiar partiallyclosed-slot construction without the use of a magnetic wedge or like structure.

In dynamo-electric machines, such as phase converters and the like, the high-frequency currents flowing in the closed circuit Windings make it desirable to position such windings as near the surfaces of the cores as is'consistent with reliable operationand economic design. My invention provides a winding which may be positioned near the surface of the core and have closed circuit ing connectors which will not materially interfere with accessibility to the energizing winding.

Figure 1 of the accompanying drawing is a side view, partially in section and 'partially in elevation, of a portion of a dy namo-electric machine embodying. myinvention; Fig. 2 is an end view, partially in section and partially in elevation, of a ortion of the structure shown in Fig. 1; ig. 3 shows a modified form of close circuiting means applicable to a winding of the type shown in Fig. 1; Fig. 4 shows a modified scheme for arranging the independent windings in a single slot; and 5 shows a modified means for permanently close circuiting the bar winding.

The portion of a dynamo-electric machine shown in Fig. 1 comprises a spider member 1, a core member 2 having a plurality of coil-containing slots 3 and a radial opening 4 between portions of the core, an energizing winding 5 and an improved form of permanently closed circuit bar winding 6. The core member 2 is assembled between end plates 7 and 8 and is rigidly clamped in position upon the spider member 1 by means of an end ring 9. The energizing winding 5 may be of any well-known form and is shown as of a familiar machine wound type having a plurality of' conductors 10 that are insulated from the core member by insulation 11. The improved form of bar winding 6, shown in Figs. 1 and 2, is disposed in offset recesses 12 near the mouths of the slots 3, and is insulated from the core member by insulation 13. The ends of the respective bars 6 are bent inwardly and are electrically connected to closed circuiting rings 7 which also con-' stitute the end plates between which the,

laminations of the core member 2 are clamped. The end portions of each of the bar members 6 are provided with slits 14: to increase their flexibility whereby they may absorb changes in the length of the bar that may be produced by-changes in the temperature thereof and thereby avoid the abnormal strains upon the end connectors which would otherwise result. Fig. 3 shows a modified form of connection for close circuiting the bar members 6. Radially extending portions 15' of the resistance ring 7 are twisted into planes at right angles to the plane of the body portion of'the ring and, are electrically connected to the sides of the bars 6. This structure is more compact than that shown in F ig. 2 and requires less material-in the end connectors 15. The bases 21 of the portions 15 are made sufficiently flexible to absorb strains produced by temperature changes.

In-F1g. 4, the .bar winding is sliown as taining wedge for the coil 5. The closedcircuiting connectors are bent similarly to those shown in Fig. 8 but are separable from the main resistor ring 7 and are se cured to the outer faces of the bars 6. Fig. 5 shows a modified form of connector which is secured to the under side of the bar 6. The offset recesses 17 and 18 of the slot are of different depths to provide sufficient area for properly securing the connector 15 to the bar 6 without causing the connector to encroach upon the portion of the slot provided for the main Winding. In this design, the slot is of the partially-closed type and, therefore, no magnetic strip 16 is required.

To assemble such a structure as I have illustrated in Figs. 1, 2 and 3; the bars 6, after being bent to the form shown in the drawing, are positioned in the recesses 12 of the slots provided therefor and are welded or otherwise secured to the resistance ring 7 The main winding is positioned in a usual way and the wedges 20 are inserted. The main winding, is entirely independent of the closed-circuit winding and may be independently removed. In Figs. 4 and 5, the main winding should be first inserted and the bar member 6 driven in place to retain the coil 5. In this arrangement of wind ings, the connectors 15 are applied last.

Although I have described myinvention in a simple and preferred form it is not necessarily so limited. I desire, therefore, that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. In a dynamo-electric machine, the combination with a slotted magnetizable core, of a plurality of independent windings of different types disposed within the same slots upon said core, and a plurality of connecting means for one of said windings eX- tending intermediate adjacent coil sides of the straight coil portions of the other winding.

2. In a dynamo-electric machine, the combination with a magnetizable core having a plurality of slots, of a main winding and bar conductors disposed within the same slots. and means disposed in the space formed between adjacent coils of the main winding and the ends of the core for close circuiting said bar conductors.

3. In a dynamo-electric machine, the combination with a magnetizable core having a plurality of slots, of a magnetizing winding having a plurality of groups of coil sides disposed within said slots, a plurality of bars disposed within the same slots and nearer the surface of said core than a portion of,

the said coil sides within each slot, and

.means disposed between adjacent slots for close circuiting said bars.

Latest? 4. In a dynamo-electric machine, the combination with a magnetizable core, of a magnetizing winding and bar conductors disposed upon said core, means for permanently close circuiting said bar conductors comprising a ring and a plurality of connecting means for connecting said bar conductors to said ring and extending intermediate adjacent coil sides of said magnetizing winding.

5. In a dynamo-electric machine, the combination with a magnetizable core having a plurality of slots, of a main winding having groups of coil sides disposed within said slots, and bar conductors disposed at the side of the main winding within the same slots and disposed in a recess near the surface of said core of less radial depth than the slots containing the main windings.

6. In a dynamo-electric machine, a magnetizable coremember having a coil-containing slot and a plurality of independent windings within said slot, said slot having an offset recess therein and one of said windings being disposed within said recess.

7. In a dynamo-electric machine, a magnetizable core member having a coil-containing slot, a main winding disposed within said slot, said slot having an offset recess therein, and a bar winding disposed within said recess and each of the bars having a slit end portion.

8. In a dynamo-electric machine, the combination with a magnetizable core member having a plurality of slots therein, of a plurality of bar members disposed within said slots and each bar member having slitted end portions bent from the ends of the core slots toward the axis of the machine.

9. A dynamo-electric machine comprising a magnetizable core having a plurality of slots, each of said slots having an offset recess near the mouth thereof, a magnetizing winding disposed within said slots, bar conductors disposed within said offset recesses,

and means disposed between adjacent slots for close-circuiting said bar conductors.

10. In a dynamo-electric machine, the combination with a slotted core member, of a bar winding disposed upon said core member and having end rings disposed between the bottoms of the core slots and the axis of the core member, and bars having their ends bent to engage said rings, the ends of-each bar being slit to provide elastic end connectors between the straight bar portions and the rings.

11. In a dynamo-electric machine, the combination with a slotted core member, of U-shaped bar conductors having" their straight solid middle portions disposed within the core slots and having the bent portions cylinder formed by the straight portions of said bars and adapted to be connected to the inwardly bent ends of said bars.

12. In a dynamo-electric machine, the

5 combination with a slotted core member, of

U-shape bar conductors each having a straight solid middle portion disposed within said core siot and having the bent end portion slotted.

In testimony whereof I have hereunto 10 subscribed my name this 3d day of March, 1916.

RUDOLF E. HELLMUND. 

